Dragon Ball Z, Volume 1 (v. 1)

In the first volume of Dragon Ball Z, Goku discovers that his Saiyan enemy Raditz is really his brother Goku must rescue his son, Gohan, from Raditz. But the adventure turns fatal, and with Goku in the afterlife, Goku's former arch-enemy, Piccolo, must begin training Gohan to follow in his father's footsteps.